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Table of Contents
ORIGINAL ARTICLE
Year : 2021  |  Volume : 4  |  Issue : 4  |  Page : 99-104

Foam sclerotherapy for below knee varicosities after great saphenous ligation and stripping: Comparison of multiple injections with infusion


1 Zhongshan School of Medicine, Sun Yat-Sen University, Haizhu, Guangzhou, Guangdong Province, China
2 Zhongshan School of Medicine; Department of Vascular Surgery, The First Affiliated Hospital, Sun Yat-Sen University, Haizhu, Guangzhou, Guangdong Province, China
3 Department of Cardiovascular Surgery, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Haizhu, Guangzhou, Guangdong Province, China

Date of Submission17-Feb-2021
Date of Decision17-May-2021
Date of Acceptance21-May-2021
Date of Web Publication19-Oct-2021

Correspondence Address:
Dr. Kai Huang
Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, No. 33, Yingfeng Road, Haizhu District, Guangzhou 510 000, Guangdong Province
China
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/2589-9686.328157

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  Abstract 


AIMS: This study aimed to compare the short-term clinical results of multiple foam sclerosant injection (MFSI) and endovenous foam sclerosant perfusion (EFSP) for treating varicose veins (VV) in the lower extremities through.
SUBJECTS AND METHODS: The study included 111 cases. All patients had high saphenous ligation and stripping just before the foam injection. First-stage sclerotherapy effects, sclerosant dosage, postoperative complications, and other clinical assessments were included as observation items with at least 6 months of follow-up.
RESULTS: The treatment effects of the 2 VV treatment methods showed no significant difference (P < 0.05) during primary closure. However, EFSP requires a lower sclerosant dosage, resulting in a lower occurrence of thrombophlebitis than that with MFSI (P < 0.05). In the follow-up period, no significant difference in recurrence rate was found between the groups (P > 0.05). Although superficial thrombophlebitis and pigmentation occurred in both groups, the EFSP group appeared to be more prone to remission (P < 0.05), as there were no vein-puncture injuries or factors to cause local hematoma. Superficial thrombophlebitis and skin pigmentation were less in the EFSP than the MSFI group (4.4% vs. 16%; P = 0.033 and 8.8% vs. 30.2%; P = 0.004, respectively).
CONCLUSIONS: Both MFSI and EPSP visibly affect VV in the lower extremities, but when complications and the simplicity and reproducibility of operation techniques are considered, EFSP appears more worthy of promotion.

Keywords: Lower extremities, sclerotherapy, varicose vein


How to cite this article:
Xia Z, Yao C, Shen R, You G, Huang K. Foam sclerotherapy for below knee varicosities after great saphenous ligation and stripping: Comparison of multiple injections with infusion. Vasc Invest Ther 2021;4:99-104

How to cite this URL:
Xia Z, Yao C, Shen R, You G, Huang K. Foam sclerotherapy for below knee varicosities after great saphenous ligation and stripping: Comparison of multiple injections with infusion. Vasc Invest Ther [serial online] 2021 [cited 2022 Aug 19];4:99-104. Available from: https://www.vitonline.org/text.asp?2021/4/4/99/328157




  Introduction Top


Primary varicose veins (VV) in the great saphenous vein (GSV) are the most common vascular disease.[1] Serious cases may result in venous hemorrhage, superficial thrombophlebitis, and even deep venous thrombosis.[1],[2] Thus, early diagnosis and treatment are advocated. Among the many methods available, the most universally acknowledged standard treatment for VV caused by GSV incompetence remains the high ligation and stripping of the GSV.[2] However, the treatment for VV in the lower extremities below knee still remains controversial. Methods ranging from subcutaneous excision methods, such as transilluminated powered phlebectomy, to minimally invasive methods.[3] The latter methods are minimally invasive and mainly cause endothelial injuries in the desired vessel, leading to nonthrombotic venous sclerosis and fiber cord formation that is gradually absorbed by the body.[4] However, this approach is relatively expensive and requires more complex operator training.

The improved technique of foam sclerotherapy (FS) is available for the treatment of VV in the lower extremities; this economical, simple, and stable method of operation has become more acceptable for patients.[5] However, considerable concern remains regarding the treatment of the GSV due to its size. Various studies on the treatment and improvement of FS for the lower extremities has been performed, and the most popular first-line method is ultrasound-guided FS (UGFS).[2],[5],[6],[7] However, even with ultrasound guidance, the surgery is often performed under repeated ultrasonic positioning and uses multiple puncture points due to operational and technical difficulties. The most common side effects of FS are thrombophlebitis and skin pigmentation, which are commonly seen when using multiple puncture points.[8] The use of multiple puncture points may cause not only local hematoma but also multiple vein injuries that cause vascular thrombosis, which may alter the sclerosing effect and often lead to the reoccurrence of VV in the original area.[9] In addition, multi-point punctures may also increase the total dose used for FS, possibly leading to systemic side effects.

By perfusing the sclerosant directly into the VV, complete occlusion can be more conveniently achieved with minimal trauma and fewer complications. The main aims of this study were to compare the methods of multiple foam sclerosant injection (MFSI) and endovenous foam sclerosant perfusion (EFSP) performed after ligation and stripping of the GSV and to evaluate the short-term clinical effects of these two methods.


  Subjects and Methods Top


Case selection

This study analyzed cases involving GSV ligation and stripping. A total of 111 cases of direct FS and multiple-puncture-point FS in the lower extremities were collected from January 2014 to October 2016 at the Department of Vascular and Thyroid Surgery at the Sun Yat-sen Memorial Hospital of Sun Yat-sen University. In each case, the patient underwent duplex scanning examination and was rated according to the (clinical, etiology, anatomy, and pathophysiology [CEAP]) classification system.

The inclusion criteria were as follows: (1) CEAP grade C2 or C3, C4-grade cases of mild ankle edema, or cases in which VV were not visible when symptomatic leg was raised while the patient remained in a supine position; (2) ultrasound-scored saphenofemoral reflux of <0.5 s along with deep vein patency; and (3) willingness of the patient to undergo follow-up.

The exclusion criteria were as follows: (1) VV diameter >8 mm in the standing position; (2) medical history of deep venous thrombosis or pulmonary embolism; (3) age less than 18 years; (4) congenital heart disease or cardiopulmonary insufficiency, especially patent foramen ovale; and (5) the condition being combined with superficial venous thrombosis.

The cases were divided into two groups according to the treatment method used, namely, the EFSP and MFSI groups.

Ethics approval

This study was performed in accordance with the ethical standards enumerated in 1975 and revised in the 1983 Declaration of Helsinki and was approved by the local ethics committee at our hospital. Informed consent was given to all patients included in this study.

Preparation of the sclerosant

The sclerosant foam was prepared using 1% Lauromacrogol (Tianyu Pharmaceutical Co., Ltd., Shanxi, China) according to Tessari's method. The foam was freshly prepared for each use by mixing 2 ml of lauromacrogol with air at a 1:4 sclerosant-to-air ratio to create 10 ml of foam sclerosant. Three 10-ml syringes were attached to a 3-way stopcock; this apparatus was used to mix the sclerosant with air to create the foam, which was prepared immediately before use.

Surgical methods

All patient procedures occurred in the operating room. Routine monitoring was performed, including cardiography and measurements of oxygen saturation and blood pressure. For the FS procedure, patients were placed in a supine position and received local anesthesia. A tourniquet was bound at the proximal end of operated leg. Before injection of the sclerosant, the VV were located and carefully marked. Each varicose tributary was injected with 2 ml of 1% foam (the maximal volume).

Before surgery, the patients were asked to take 10-min walks; VV were located and marked afterward.

Each varicose tributary was injected with 2 ml of 1% foam (the maximal volume).

In the MSFI group, each patient was placed in a standing position in the operating room, and the indwelling needles (22-Ga Becton Dickinson Infusion Therapy Systems Inc., USA) in the punctured veins were fixed with tape (each point was approximately 4 cm from the others). There were usually no more than five indwelling needles, and the retention standard was that blood could be seen on withdrawal; saline was injected to confirm that the blood was intravenous.

Electrocardiography, blood oxygen saturation, blood pressure, and heart rate were closely monitored throughout the operation. The patients were treated with lumbar spinal anaesthesia and then placed in a supine position; the leg was raised for routine surgical area disinfection and draping (the leg was raised for at least 10 min to ensure venous collapse). A 2-cm transverse incision was made at the groin crease just medial to the femoral artery pulse point; after all tributaries had been exposed by dissection, they were identified and flush-ligated to minimize the incidence of reflux recurrence. The GSV was then transected and ligated 0.5 cm from the femoral vein. The stripping instrument was then inserted into the GSV at the groin and threaded through the incompetent vein to the level of the upper calf. There, a 1-cm incision was made near the tibial tuberosity at the knee, where an inverting head was secured to the proximal end of the vein. The GSV was then pulled out through the incision made in the upper leg, and the intradermal suture of the incision was coated with glue (FAL, Beijing, China).

The leg was again raised for 5 min, and the indwelling needles were examined to observe whether they met the retention standard before injecting the foam sclerosant. Each indwelling needle was injected with no more than 2 ml of foam sclerosant at each puncture point. The blood flow at the affected areas was observed through the filling of sclerosant both in the veins and by ultrasound.

In the EFSP group, after performing standard disinfection and draping of the surgical area, the same method described above was applied to the trunk of the GSV, except that 4 cm of ligature was retained at the distal end of the vein on the inner side below the knee. The leg was raised as the tourniquet was applied at the proximal end of the thigh. After laying down the leg and loosening the ligature, a catheter was inserted into the distal end of the vein, and a small amount of normal saline was injected to check for leakage and misplacement. The foam sclerosant was then perfused into the vein, while the areas containing the marked veins were massaged from their proximal to their distal ends. The total dose of foam sclerosant was noted when the distal ends of the marked veins were filled (filled and dilated marked veins are palpable). The total foam volume was typically no more than 8 ml, but in cases of larger VV distribution, 1-cm incisions were made on the surface of the marked vein for re-ligation of the proximal end and injection of FS at the distal end; temporary pressure bandaging was then applied to the area with gauze. The GSV trunk was then extracted, and an intradermal suture was applied and coated with tissue glue before the immediate application of pressure bandaging with cotton pads.

After 48 h of cotton pad pressure bandaging, the pads were replaced with thigh-high compression stockings. In addition, all patients were asked to perform out-of-bed ambulation 6 h after surgery and were required to wear compression stockings for approximately 1 month.

Two weeks after surgery, if the original VV were visible after 10 min of standing or walking, a second injection was made. All patients were required to undergo postoperative follow-ups in the first and 3rd month after the first- and second-stage surgeries.

Follow-up

Follow-up included the assessment of patient recovery, physical examination, and color Doppler ultrasound. Color Doppler ultrasound was mainly used to check for superficial or deep vein thrombosis, residual reflux or residual VV. In addition, VV occlusion, complications, and recovery time were compared between the two groups at the first stage after the operation. However, due to the relatively short follow-up time, we mainly relied on patient inquiries about their condition. The patients asked about pain symptoms, fatigability, heaviness, recurrent superficial thrombophlebitis, newly found pigmentation, or linear sclerosis in the affected leg.

Statistical analysis

All data were entered into an MS Excel spreadsheet (Microsoft, Bellevue, WA, USA). The data were analyzed using IBM SPSS Statistics ver. 23.0 (IBM Co., Armonk, NY, USA) to compare the clinical outcomes of each treatment modality. Nonparametric analysis was used for drawing comparisons between the two groups (Mann–Whitney U-test), and a Chi-squared contingency table analysis was used for frequency analysis. Data were reported as standard deviation. A P < 0.05 was considered statistically significant.


  Results Top


This study included a total of 111 patients with VV in their lower extremities between January 2014 and October 2016. These patients were diagnosed with primary VV in the lower extremities according to their medical histories and ultrasound reports. The average age of the patients was 54.45 ± 12.52 years, and the average disease duration was 9.93 ± 4.23 years. Both groups underwent high ligation of the GSV under lumbar anaesthesia that was followed by a subcutaneous incision on the inner knee to strip away the saphenous vein trunk. Two groups were formed according to the type of sclerosant treatment method used, namely an EFSP group comprising 68 patients and an MFSI group comprising 43 patients. Factors that might increase venous hypertension, such as body mass index and disease course, did not statistically differ between the two groups. Three experts from this center performed treatments for both groups. Patients in both groups suffered from simple VV (C2) without symptoms of edema or pigmentation (C3 and C4); even those cases classified as C3 or C4 were mild. Surgeons have reached a consensus that EFSP and MFSI are most suitable for early-and middle-stage (C2-C3) or mild C4 patients and for cases in which the VV disappear when the affected leg is raised. This study included 35 cases of mild edema in the lower extremities, 15 cases of mild pigmentation, and no cases with venous ulcers or superficial venous thrombophlebitis. The relative proportions of such cases did not statistically differ between the two groups [Table 1].
Table 1: Baseline characteristics of endovenous foam sclerosant perfusion and multiple foam sclerosant injection group

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Residual treatment or reversal should be considered if the VV are clearly visible and soft. Two weeks after the initial operation in both the EFSP and MFSI groups, only 8 and 5 cases, respectively, required second-stage sclerotherapy at the previously marked areas, as shown in [Table 2]. These cases were similar in that they had relatively long medical histories and widely distributed VV, which can lead to incomplete occlusion and reversal. Significantly more patients in the MFSI group than in the EFSP group experienced superficial thrombophlebitis; this discrepancy may have been caused by technical differences. In general, the treatments applied to both groups showed similar effectiveness (no statistically significant difference was observed; P = 0.983); however, patients in the EFSP group were given much lower foam sclerosant dosages than those in the MFSI group (P < 0.01). These 13 patients agreed to accept second-stage sclerotherapy and recompression treatment, and neither residual symptoms nor reversal were observed during the 2-week follow-up.
Table 2: Results of sclerotherapy in endovenous foam sclerosant perfusion and multiple foam sclerosant injection group

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These cases were followed up for at least 6 months after surgery; if the VV remained obvious and soft at the original marked areas, it was considered recurrence. As shown in [Table 3], the recurrence rate was lower for patients in the EFSP group after 6 months of follow-up, although the difference between the two groups was not significant (P = 0.953). The lack of significance may have been caused by the small number of cases; there were only 3 cases of recurrence. The sites of recurrence were mainly located in the middle segment of the calf in both groups. After consultation, all the patients agreed to accept secondary sclerotherapy.
Table 3: Postoperative results of endovenous foam sclerosant perfusion and multiple foam sclerosant injection group

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By then, superficial thrombophlebitis had dissipated for only some of the patients. Patients who did not achieve complete remission were mainly found in the MFSI group, and the difference between the two groups was statistically significant. According to clinical observations, some of these cases achieved remission in the subsequent 6 months, while others were relieved after receiving thrombus aspiration by puncture or recompression. Mild pigmentation appeared more often in the MFSI group (30.23%), and the difference was statistically significant (P = 0.07). Nevertheless, the pigmentation was localized and scattered, and it gradually improved through the use of Hirudoid (DALLCL SANKYO EUROPE GmbH, Germany) and Aescuven Forte (Julius Redel Cesra, Germany) treatment.

During the follow-up period, hematoma or subcutaneous ecchymosis occurred only in the MFSI group; this finding might be due to differences in technique between the two groups. Fortunately, there were no cases of skin necrosis. None of the patients experienced side effects associated with FS, such as migraine headaches and chest discomfort, or serious complications, such as deep vein thrombosis or pulmonary embolism, during the perioperative and follow-up periods.


  Discussion Top


FS is currently a popular and minimally invasive method for the treatment of VV of the lower extremities.[10] By causing endothelial injury in the desired vessel, which results in a clot that blocks blood circulation in the vein beyond, the sclerosant causes the clotted vein to lose function and be replaced with fibrous tissue that is gradually absorbed by the body. Despite restrictions regarding the diameter of the diseased vein, FS remains an effective, safe, minimally invasive and cost-effective method to “chemically remove” the affected veins.[6]

In clinical practice, foam sclerosant injection techniques vary amongst medical centers. However, UGFS remains the most popular method. While it is efficient, safe and accurate, UGFS requires operators to be experienced in both puncture and ultrasound.[11] Furthermore, complications such as superficial thrombophlebitis and local hematoma caused by puncture and ultrasound-positioning errors are unavoidable. Therefore, we have made modifications to this technique based on the medical conditions in our center. Each patient was placed in a standing position after their VV had been marked; multi-point punctures were performed on marked veins that extruded more obviously; and indwelling needles were left in the patient to inject sclerosant (as mentioned above). In practice, we also found that EFSP can be effective for the treatment of VV; the involved techniques include opening up the vein cavity directly and inserting the catheter for perfusion. We found in early practice that in cases of obvious circulation insufficiency in lower extremity veins, this method may lead to an increased risk of deep vein thrombosis. Therefore, this study selected only early to mid-term cases (C2–C3) and C4-grade cases of mild ankle edema and cases in which the VV were no longer visible when the injured leg was raised while the patient was in a supine position. These cases are similar in that they involve a larger distribution of VV, a smaller vein lumen and remaining vein elasticity.

Nevertheless, despite the differences between the two groups in terms of operational technique, they achieved similar results in first-stage cases. Because the sclerosant needs maximal contact with the vessel linings to achieve the best effect, the patient should be in a standing position while leaving the puncture needles indwelling; the affected legs should then be raised with the patient in a supine position to reduce vein blood flow before injecting the sclerosant. However, the sclerosant cannot effectively decrease venous reflux; therefore, the foam sclerosant becomes mixed with a considerable amount of blood, which may explain the high occurrence of postoperative superficial thrombophlebitis.[12] Furthermore, if thrombus organization and recanalization occurs or if the foam sclerosant does not completely contact the vein intima, the VV can reappear. However, EFSP has unique advantages in this regard. First, EFSP is performed under lumber anaesthesia, thus avoiding the pain of puncture and discomfort caused by local hematoma or puncture injury, making EFSP more comfortable for patients, which is why more patients were in this group. Second, after high ligation of the GSV, raising of the affected limb and fixing of the tourniquet to ensure the collapse of the VV and thus their drainage, the sclerosant is perfused into the veins. This method can reduce the mass of the targeted VV so that the sclerosant can contact the most target VV while using a minimal amount of sclerosant. After treatment, the therapeutic effects achieved in the two groups were equivalent, and residual vein occurrence did not significantly differ between the groups; however, the EFSP group required an evidently lower sclerosant dosage than the MFSI group, possibly because the veins contained residual blood and because venous reflow from the communicating branches resulted in increased flow resistance to the sclerosant. This may also explain the significant increase in the superficial thrombophlebitis occurrence rate in the MFSI Group 2 weeks after the operation. In contrast, superficial thrombophlebitis and residual VV were also unavoidable in the EFSP group. Some studies have suggested that instead of mixing the sclerosant with air, other gases might increase the fluidity of the foam sclerosant; this area of investigation may result in the improvement of the EFSP procedure. Possible cases of residual veins and recanalization were used as indications for secondary intervention, and this possibility was thoroughly explained to patients before the operation to encourage each patient to attend a follow-up appointment 2 weeks after the operation.[6],[7],[8],[9]

For the secondary treatment, the UGFS method was used to perform a second injection in patients with residual VV. For patients with superficial thrombophlebitis, after drawing out the thrombosis using a syringe, the leg was compressed and treated with Aescuven forte. Three months later, few patients had relapsed, and no statistically significant difference was found between the two groups, indicating that both methods were effective in our center. However, EFSP resulted in fewer complications. After secondary treatment, patients with superficial thrombophlebitis were significantly less frequent in the EFSP group, possibly because no veins were injured in the first-stage operation. Superficial phlebitis was eventually relieved by this point in both groups, indicating that the complications remained controllable. However, pigmentation was inevitable in both groups. Studies have shown that pigmentation may be associated with the components of the sclerosant itself but may also be associated with local venous injury or impaired blood circulation.[13] The pigmentation was mostly located on the lower leg and was threaded along the originally marked VV, possibly corresponding to venous injuries caused by punctures. The pigmentation was generally cosmetically acceptable to the patients, possibly because of their mean age (54.45 ± 12.52 years). The EFSP group exhibited significantly less pigmentation than the MFSI group; this finding may represent one reason to promote the use of MFSI. Notably, there was no case of deep venous thrombosis or pulmonary embolism during the follow-up period in the EFSP group, and this finding may be attributed to the first-stage treatment, especially the application of evasculation and tourniquet.

Although the advantages of EFSP are clear in this study, the study has certain limitations. First, the follow-up time was relatively short and thus cannot reflect any long-term effects, complications or prognoses in the two groups after treatment. Further follow-ups are required to ascertain such information. Second, due to the research design, no strict contrast was made between the two sets of data. More-rigorous research designs must be developed for use in further studies. Moreover, the safety of direct perfusion remains controversial, as it has only been clinically observed; research on this topic has yet to perform.


  Conclusion Top


Overall, based on short-term clinical observation, both of the methods discussed in this study are suitable for early-to middle-stage VV of the lower extremities or in cases where VV are no longer visible when the affected leg is raised while the patient adopts a supine position. However, the complication rate and the reproducibility and simplicity of the operation suggest that EFSP is worthy of greater promotion.

Financial support and sponsorship

The project is sponsored by the National Natural Science Foundation of China (Project Approval Number is 81800420).

Conflicts of interest

There are no conflicts of interest.



 
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    Tables

  [Table 1], [Table 2], [Table 3]



 

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